Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product.

It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water.

An odorless and colorless emollient ester (cetyl alcohol + ethylhexanoic acid) that gives a velvety and silky feel to the skin. It has geat spreadability and a non-oily feel. It's a popular ingredient in makeup removers.

The emollient plant oil coming from the soybean. It is considered to be a nice, cost-effective base oil with moisturizing properties. As for its fatty acid profile, it contains 48-59% barrier-repairing linoleic acid, 17-30% nourishing oleic acid and also some (4.5-11%) potentially anti-inflammatory linolenic acid.

A very common emollient that makes your skin feel nice and smooth. It comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. It’s a nice ingredient that just feels good on the skin, and it’s also easy to formulate with. No wonder it’s popular.

A helper ingredient that functions as a film-forming polymer (big molecule from repeated subunits).

It usually comes to the formula as part of a thickener-emulsifier trio paired with Polyisobutene and Polysorbate 20. The three togeather have excellent thickening properties with remarkable emulsifying-stabilising abilities. They also have a nice silicone feel with glide-on spreading.

Squalane is a real goodie with great skin hydrating and emollient properties.

It occurs naturally in certain fish and plant oils, and in the sebum (the oily stuff our skin produces) of the human skin. The latter makes it an important skin-identical ingredient and a NMF (natural moisturizing factor).

One of the 9 types of ceramides that can be found naturally in the upper layer of the skin. Ceramides make up 50% of the goopy stuff that's between our skin cells and play a super important role in having a healthy skin barrier and keeping the skin hydrated.

Squalene is a great pick when it comes to skin hydration and emollients.

It’s an oily natural stuff that originally comes from shark liver but luckily it can also be found in a couple of plant oils. Olive (0.6%), peanut (0.1%) and pumpkin (0.35%) oils contain it, though not in huge amounts.

What contains more of it, is the sebum (the oily stuff) that our skin produces. About 13% of human sebum is squalene, which means that it’s an important skin-identical ingredient and NMF (natural moisturizing factor).

There is also research showing it has antioxidant properties.

On the negative side, squalene is less stable than its hydrogenated form squalane. If squalene is in the ingredient list look out for tubes and pumps that protect the product from air and light.

According to famous dermatologist, Leslie Baumann while tocopheryl acetate is more stable and has a longer shelf life, it’s also more poorly absorbed by the skin and may not have the same awesome photoprotective effects as pure Vit E.

Butylene glycol, or let’s just call it BG, is a multi-tasking colorless, syrupy liquid. It’s a great pick for creating a nice feeling product.

BG’s main job is usually to be a solvent for the other ingredients. Other tasks include helping the product to absorb faster and deeper into the skin (penetration enhancer), making the product spread nicely over the skin (slip agent), and attracting water (humectant) into the skin.

It’s an ingredient whose safety hasn’t been questioned so far by anyone (at least not that we know about). BG is approved by Ecocert and is also used enthusiastically in natural products. BTW, it’s also a food additive.

BTW, lye is not something new. It was already used by ancient Egyptians to help oil and fat magically turn into something else. Can you guess what? Yes, it’s soap. It still often shows up in the ingredient list of soaps and other cleansers.

Sodium hydroxide in itself is a potent skin irritant, but once it's reacted (as it is usually in skin care products, like exfoliants) it is totally harmless.

It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It’s not a strong one and doesn’t really work against bacteria, but more against mold and yeast. To do that it has to break down to its active form, sorbic acid. For that to happen, there has to be water in the product and the right pH value (pH 3-4).

But even if everything is right, it’s not enough on its own. If you see potassium sorbate you should see some other preservative next to it too.

Super common little helper ingredient that helps products to remain nice and stable for a longer time. It does so by neutralizing the metal ions in the formula (that usually get into there from water) that would otherwise cause some not so nice changes.

Other than having a good safety profile and being quite gentle to the skin it has some other advantages too. It can be used in many types of formulations as it has great thermal stability (can be heated up to 85°C) and works on a wide range of pH levels (ph 3-10).

It’s often used together with ethylhexylglycerin as it nicely improves the preservative activity of phenoxyethanol.

If you have spotted ethylhexylglycerin on the ingredient list, most probably you will see there also the current IT-preservative, phenoxyethanol. They are good friends because ethylhexylglycerin can boost the effectiveness of phenoxyethanol (and other preservatives) and as an added bonus it feels nice on the skin too.